Help with english translation of Ikkitousen Xross Impact PSP

I know some Japanese PSP and 360 games have text strings in a single file or more. I'm not sure which program to view the files in, and I've tried a few files in Notepad++ but I just get a whole bunch of null blocks. One file I noticed had all english characters in alphabetic order, but no Japanese characters.
Also I have attempted to change the character set to Japanese on all files but still no text strings. Is there another setting I need to use to view them?